This map has 15 levels of different difficulty that will give you a real parkour challenge. From the easy green snake to the Tower of the Masters.
This map uses lots of new Minecraft 1.12 features, such as functions and advancements, so it hasn't got giant lines of command blocks. It has a custom advancement tab that will give you some goals and challenges. Also there are hidden treasures, that you can find along your journey.
It took me three days to build this map and write all commands and files. I completed it in 2 hours (and I used some cheats), but it can take much more time to complete it, if you aren't so good at parkour as me :)
Map was made for singleplayer, but you can try and play with friends, if you don't fear of bugs. It wasn't tested in multiplayer.
Play on peaceful difficulty and DON'T CHEAT, but if you're completely hopeless in finishing a level, you can set a spawnpoint for yourself.